I bought one of these from Overstock a few years ago and it is still in excellent working condition. After reading the other reviews I just had to comment. 1) I have jumped at least 5 cars or trucks before I had to recharg. 2) A battery will not jump if there is a bad cell in the battery this is battery maintance 101. Small batteries such as lawn mowers or motor bikes only last about 12 to 18 months before they go bad.